- Postcode district
- L31
- Survey
- Free for new and replacement doors
- Typical lead time
- Typically 6–8 weeks for slimline systems after check survey sign-off
- Guide price
- From £5,095 inc VAT
- Nearby
- Kirkby, Ormskirk, Bootle
- Building rules
- England
Why choose sliding doors for extensions in Maghull?
Before you settle on a door type, it helps to know what sliding doors for extensions do well and what to check before you order.
If your Maghull builder is about to pour the screed, confirm the finished floor level for the threshold first, because it is very hard to change afterwards.
Planning an extension in Maghull? Send us the drawings before the steel is ordered, so the beam above the doors can be designed with the door in mind.
- Agreeing a fitting date with your builder lets the extension be made weathertight on programme, so plastering and flooring can follow without waiting on the doors.
- Being involved at drawing stage means the opening is formed to suit the door, rather than the door being compromised to suit an opening built a few centimetres out.
- Telling the engineer the door type and span early lets them design the beam above it to limit deflection, protecting the smooth running of large sliding panels.
Light and sun in Maghull
Because Maghull sees long summer days (about 17 h 02 min) and short winter ones (about 7 h 28 min), the elevation your door faces makes a real difference. With the midday sun at about 13° in winter, a south-facing door brings light well into the room; a west-facing door catches hot late-afternoon sun in summer.
What should you budget for sliding doors for extensions in Maghull?
These are guide prices for fitted doors, including VAT. They run from an entry-level system to a premium one at the same size; the survey confirms which suits your opening.
| Overall width | Typical panels | Guide price (fitted, inc VAT) |
|---|---|---|
| 2.4 m | 2 panels | £5,995–£7,295 |
| 3.0 m | 2 panels | £6,895–£8,395 |
| 6.0 m | 4 panels | £11,395–£13,895 |
See every size on the sliding doors for extensions page or try the guide price tool.
Survey, manufacture and fitting around Maghull
Nothing is ordered until you sign off the surveyed specification. The door is made from the finished opening sizes (typically 6–8 weeks for slimline systems after check survey sign-off), and fitting usually takes 1–2 days, scheduled to the build programme. If you are in Kirkby or Ormskirk, the same process and prices apply.
Do you need approval in Maghull?
Doors in an English extension go through the extension's Building Regulations approval. Under Approved Document L, the total area of windows, roof windows and doors is normally capped at 25% of the extension's floor area plus any openings the extension removes, unless your designer shows compensating improvements; the glass must be safety glazing under Approved Document K.
Specification choices for sliding doors for extensions in Maghull
- Flush threshold. A level floor from inside to out, with a drainage channel set into the patio.
- Two-panel slimline. One sliding and one fixed panel, suiting openings up to around 3.6 m depending on the system.
- Three or four panels. More panels for wider extension openings, with one or more sliding.
Questions about sliding doors for extensions in Maghull
Do I need building approval for sliding doors for extensions in Maghull?
In England a replacement door is a controlled fitting, so compliance is arranged through a competent person scheme installer or Building Control; new openings need a Building Regulations application. We confirm the right route for your property at survey, so the paperwork is in place before fitting.
Why does the steel beam matter for sliding doors?
The steel beam above an extension's sliding door matters because every beam bends a little under load, and a large sliding door needs a straight, level head to run freely. If the engineer knows a wide slider will sit under the beam, they can design for low deflection. Too much movement can make panels stiff or bind.
Can you measure from drawings rather than the built opening?
We can quote from drawings, but we manufacture from a check survey of the built opening, because real openings often differ slightly from the plans. Making a large made-to-measure door from drawings alone risks it not fitting. If a programme makes that unavoidable, any arrangement and who carries the risk would be agreed in writing first.
How much do sliding doors for an extension cost?
Slimline sliding doors for an extension have a guide price of £7,795–£9,495 for a 3.6 m opening and £9,595–£11,695 for a 4.8 m opening, fitted, inc VAT at standard 2.1 m height. Taller doors, extra panels, special glass and flush thresholds move the price. Your written quote after the check survey fixes it.

